title: Physiological profile of world-record-holder Sherpas.
abstract: OBJECTIVE
  Tibetans and Sherpas have long been revered for their physical aptitude at high altitude, and are thought to have lived at high altitude longer than any other culture. We performed physiologic testing on 2 Sherpas who currently hold world records for: (1) most number of ascents of Mt Everest and (2) speed ascent of Mt Everest from base camp to the summit. In doing so, we describe certain physiological aspects of these individuals that may contribute to their abilities at altitude.
  
  
  METHODS
  Anthropometric measurements, blood testing, and electro- and echocardiographic examination as well as pulmonary function tests were performed. Exercise testing consisted of treadmill climbing at increasing incline and speed while wearing a 22 kg backpack in Salt Lake City (1325 m) and Park City (2063 m).
  
  
  RESULTS
  Anthropometry, electrocardiography, pulmonary function, strength, and echocardiography were consistent with predicted parameters for the general population. The Sherpas demonstrated appropriate cardiopulmonary response to dynamic exercise similar to moderately fit individuals while performing treadmill testing, both at moderate and high altitude. As expected, the energetic cost increased at higher altitude, likely due to increased respiratory work.
  
  
  CONCLUSIONS
  The 2 world-record Sherpa climbers were within normal ranges for the specific measurements that were tested. They displayed appropriate cardiopulmonary and physiological responses and exercise performance profiles at moderate and high altitude.
authors.affiliation: Division of Emergency Medicine, University of Utah, Salt Lake City, UT 84132, USA. Scott.mcintosh@hsc.utah.edu
authors.forename: Scott E
authors.initials: SE
authors.lastname: McIntosh
authors.forename: Massimo
authors.initials: M
authors.lastname: Testa
authors.forename: James
authors.initials: J
authors.lastname: Walker
authors.forename: Stacie
authors.initials: S
authors.lastname: Wing-Gaia
authors.forename: Staci N
authors.initials: SN
authors.lastname: McIntosh
authors.forename: Sheldon E
authors.initials: SE
authors.lastname: Litwin
authors.forename: Carrie
authors.initials: C
authors.lastname: Needham
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Tabin
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D000531:Altitude; D000886:Anthropometry; D004562:Electrocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D008297:Male; D008875:Middle Aged; D009051:Mountaineering; D009390:Nepal; D012129:Respiratory Function Tests